Conventional toner image fixing apparatus employ one or more rollers which are internally heated. The largest use of an internally heated roller in such apparatus is to directly contact a toner image in a pressure nip. However, other rollers are also internally heated in some fusers. For example, it is known to heat the roller contacting the back of a receiving sheet carrying a toner image on its front and also to internally heat rollers which contact the outside surface of one or both of the nip-forming rollers to externally heat such rollers.
Typically, an internally heated roller includes a hollow metallic core in which an electrically powered lamp is positioned. The core is rotatable. For electrical contact and other reasons, the lamp is stationary. Conventionally, the opposite ends of the lamp are fixed to the frame of the apparatus and essentially suspended along the roller axis of rotation in the cavity. Assembly or replacement of a roller or lamp generally requires installation of the roller, positioning of the lamp inside the roller and attaching of the lamp at both ends to the frame.